Dr. Marv Coarse Diamond Sharpening Stones [80, 60, 40 µm]

Dr. Marv's Scientific Sharpening Stones, Coarse Set. Resin-bond diamond stones, handmade by Dr. Marv in the German Alps, in the 1" x 6" size for fixed-angle sharpeners.

What it's for

Setting a new bevel, repairing chips and reprofiling. Dr. Marv makes the coarse stones with a reformulated, heat-tempered bond that's harder than his medium and fine stones, plus a higher diamond concentration, so they hold up to heavier work.

What's in the set

• 80 µm
• 60 µm
• 40 µm

Stones are rated by their nominal diamond particle size in microns (µm), the way Dr. Marv tests and publishes them.

How they're made

• Diamond abrasive in a resin bond on an anodized aluminum blank
• Each surface is dressed with a single-point diamond chisel instead of conventional flattening
• Use with a honing oil, which is how Dr. Marv tests his stones

From Dr. Marv's testing

In his own review, the 80 µm stone left a smooth, even bevel with a slightly toothy apex, a good fit for outdoor and hard-use knives. Read his 80 µm study or the 60 µm and 40 µm studies.

A message from Dr. Marv

1x Stone 80 μm
1x Stone 60 μm
1x Stone 40 μm
Size of the Aluminum Blank: 159 x 25 mm x 3 mm
Size of the Abrasive Layer: 150×25 + At least 4 mm thickness
Diamond Concentration: >65% by weight!

These are the “Dr. Marv’s Scientific Sharpening Stones”. They have anunheard of concentration and are absurdly pure and contamination free.This was achieved by very tight, electron microscopy quality control,followed by manufacturing in a laminar flow box. Dressing is done via singlepoint diamond chiseling, which also stops any contamination. Moreover,every set is diamond chiseled individually in the same fixture, so thestones are very, very close in their thickness. I personally do not feel theneed to adjust the angle when switching from one stone to the next.

Their development is based on my scientific research into abrasives. Ifirmly believe that these are super high performing abrasives!

I am very proud to say that the resin, filament, foam, chemicals andaluminium are Made in Germany. Machining of the aluminium blanks wasdone in Germany. Only the diamond is imported, but meticulously quality

As this is a handmade product, some small blemishes such as tiny bubbles, scratches or imperfections are to be expected. I can promise that they do not subtract from the performance of the sharpening stones!